Resource query and control

,collectInvoke the garbage collector. Ordinarily this happens
automatically, but the command tells how much space is available
before and after the collection.

,keep kind

,flush kindThese control the amount of debugging information retained after
compiling procedures. This information can consume a fair amount
of space. kind is one of the following:

maps - environment maps (local variable names, for inspector)

source - source code for continuations (displayed by inspector)

names - procedure names (as displayed by write and in error
messages)

files - source file names

These commands refer to future compilations only, not to procedures
that already exist. To have any effect, they must be done before
programs are loaded. The default is to keep all four types.

,flushThe flush command with no argument deletes the database of names
of initial procedures. Doing ,flush before a ,build or
,dump
will make the resulting image significantly smaller, but will
compromise the information content of many error
messages.